Evaluation of Myocardial State by Synchronized Radiography and Exercise

Abstract

ALTHOUGH cardiac response to exercise has been studied in many ways, the immediate changes in heart size have received little attention, and almost no clinical application. Normal laboratory animals have consistentlv responded to exercise with an immediate reduction in cardiac diameter.¹ Except for early, inconsistent radiographic studies² observations of the immediate effects of exertion upon the heart size of man have been limited to a few measurements employing operative or technical procedures so complex as to limit their application sharply. The results, however, have proved consistent. Radiographs of 4 hearts marked with metal clips at thoracotomy exhibited a reduction in . . .